/*- * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Berkeley Software Design Inc's name may not be used to endorse or * promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $ * $FreeBSD$ */ #ifndef _MACHINE_MUTEX_H_ #define _MACHINE_MUTEX_H_ #ifdef LOCORE /* * Simple assembly macros to get and release non-recursive spin locks */ #define MTX_ENTER(lck) \ mfmsr r10; \ /* disable interrupts */ rlwinm r0, r10, 0, 17, 15; \ mtmsr r0; \ 1: li r11, MTX_LOCK; \ /* MTX_LOCK offset */ lwarx r0, r11, lck; \ /* load current lock value */ cmplwi r0, r1, MTX_UNOWNED; \ /* compare with unowned */ beq 1; \ /* if owned, loop */ lwz r0, PC_CURPROC(pcpup); \ /* load curproc */ stwcx. r0, r11, lck; \ /* attempt to store */ beq 1; \ /* loop if failed */ sync; \ /* sync */ eieio; \ /* sync */ stw r10, MTX_SAVEINTR(lck) /* save flags */ #define MTX_EXIT(lck) \ sync; \ /* sync */ eieio; \ /* sync */ li r0, MTX_UNOWNED; \ /* load in unowned */ stw r0, MTX_LOCK(lck); \ /* store to lock */ lwz r0, MTX_SAVEINTR(lck); \ /* load saved flags */ mtmsr r0 /* enable interrupts */ #endif /* !LOCORE */ #endif /* __MACHINE_MUTEX_H */